光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2014年
8期
2152-2156
,共5页
翟秋阁%郭鹏%周琳%刘彦明
翟鞦閣%郭鵬%週琳%劉彥明
적추각%곽붕%주림%류언명
氧化石墨烯%亚甲基蓝%荧光光度法%铋(Ⅲ)离子
氧化石墨烯%亞甲基藍%熒光光度法%鉍(Ⅲ)離子
양화석묵희%아갑기람%형광광도법%필(Ⅲ)리자
Graphene oxide%Methylene blue%Spectrofluorimetry%Bi3+
在水溶液中，氧化石墨烯（Go）对亚甲基蓝（CMB）的荧光可产生猝灭作用，加入适量Bi3＋可使体系的荧光增强，且增强程度与Bi3＋的加入量有关。氧化石墨烯含有大量的含氧官能团使之表面带负电荷，易于分散在水中。带正电荷的荧光染料亚甲基蓝通过静电引力和π-π堆积作用吸附在GO表面，形成了GO-MB复合物，从而产生荧光猝灭。使用改进的 Hummers制备了氧化石墨烯，应用扫描电子显微镜（SEM）和透射电子显微镜（TEM）对制备的GO进行了表征。利用紫外可见吸收光谱验证了石墨烯与亚甲基蓝的作用过程，结果表明亚甲基蓝的荧光猝灭后，其两个主要吸收峰强度明显降低，而且GO的吸收光谱与MB的发射光谱完全不同，重叠度太小，不能发生能量转移，因此，GO 与 MB发生的荧光猝灭属于静态猝灭过程。当向亚甲基蓝氧化石墨烯络合体系加入Bi3＋后，由于Bi3＋体积小，带正电荷多从而取代了亚甲基蓝致使亚甲基蓝脱离氧化石墨烯，荧光恢复，荧光恢复的程度随Bi3＋量的增加而增强，据此建立了氧化石墨烯-亚甲基蓝荧光光度法测定Bi3＋的新方法。考察了亚甲基蓝、氧化石墨烯浓度，酸度以及试剂加入顺序对体系荧光恢复的影响，该络合体系的激发波长为667 nm，发射波长为690 nm，在优化条件下，Bi3＋的浓度在0．5～100μmol·L-1范围内与荧光强度呈良好的线性关系，相关系数为0．9955。方法的检出限为1．0×10-8 mol· L-1（S/N＝3）。评价了该方法的选择性，结果表明当共存离子为1000倍的K＋，Ca2＋，Na＋，Mg2＋，Cu2＋；100倍的Fe3＋，Be2＋，SiO2-3，Al3＋，Ni2＋，Sb3＋，NO-3，Cl-，F-；20倍的Pb2＋，Hg2＋，Cd2＋不干扰Bi3＋的测定，新方法具有灵敏度高、快速、成本低等优点，将提出的方法用于环境水样的分析，回收率为93．4％～105．2％。
在水溶液中，氧化石墨烯（Go）對亞甲基藍（CMB）的熒光可產生猝滅作用，加入適量Bi3＋可使體繫的熒光增彊，且增彊程度與Bi3＋的加入量有關。氧化石墨烯含有大量的含氧官能糰使之錶麵帶負電荷，易于分散在水中。帶正電荷的熒光染料亞甲基藍通過靜電引力和π-π堆積作用吸附在GO錶麵，形成瞭GO-MB複閤物，從而產生熒光猝滅。使用改進的 Hummers製備瞭氧化石墨烯，應用掃描電子顯微鏡（SEM）和透射電子顯微鏡（TEM）對製備的GO進行瞭錶徵。利用紫外可見吸收光譜驗證瞭石墨烯與亞甲基藍的作用過程，結果錶明亞甲基藍的熒光猝滅後，其兩箇主要吸收峰彊度明顯降低，而且GO的吸收光譜與MB的髮射光譜完全不同，重疊度太小，不能髮生能量轉移，因此，GO 與 MB髮生的熒光猝滅屬于靜態猝滅過程。噹嚮亞甲基藍氧化石墨烯絡閤體繫加入Bi3＋後，由于Bi3＋體積小，帶正電荷多從而取代瞭亞甲基藍緻使亞甲基藍脫離氧化石墨烯，熒光恢複，熒光恢複的程度隨Bi3＋量的增加而增彊，據此建立瞭氧化石墨烯-亞甲基藍熒光光度法測定Bi3＋的新方法。攷察瞭亞甲基藍、氧化石墨烯濃度，痠度以及試劑加入順序對體繫熒光恢複的影響，該絡閤體繫的激髮波長為667 nm，髮射波長為690 nm，在優化條件下，Bi3＋的濃度在0．5～100μmol·L-1範圍內與熒光彊度呈良好的線性關繫，相關繫數為0．9955。方法的檢齣限為1．0×10-8 mol· L-1（S/N＝3）。評價瞭該方法的選擇性，結果錶明噹共存離子為1000倍的K＋，Ca2＋，Na＋，Mg2＋，Cu2＋；100倍的Fe3＋，Be2＋，SiO2-3，Al3＋，Ni2＋，Sb3＋，NO-3，Cl-，F-；20倍的Pb2＋，Hg2＋，Cd2＋不榦擾Bi3＋的測定，新方法具有靈敏度高、快速、成本低等優點，將提齣的方法用于環境水樣的分析，迴收率為93．4％～105．2％。
재수용액중，양화석묵희（Go）대아갑기람（CMB）적형광가산생졸멸작용，가입괄량Bi3＋가사체계적형광증강，차증강정도여Bi3＋적가입량유관。양화석묵희함유대량적함양관능단사지표면대부전하，역우분산재수중。대정전하적형광염료아갑기람통과정전인력화π-π퇴적작용흡부재GO표면，형성료GO-MB복합물，종이산생형광졸멸。사용개진적 Hummers제비료양화석묵희，응용소묘전자현미경（SEM）화투사전자현미경（TEM）대제비적GO진행료표정。이용자외가견흡수광보험증료석묵희여아갑기람적작용과정，결과표명아갑기람적형광졸멸후，기량개주요흡수봉강도명현강저，이차GO적흡수광보여MB적발사광보완전불동，중첩도태소，불능발생능량전이，인차，GO 여 MB발생적형광졸멸속우정태졸멸과정。당향아갑기람양화석묵희락합체계가입Bi3＋후，유우Bi3＋체적소，대정전하다종이취대료아갑기람치사아갑기람탈리양화석묵희，형광회복，형광회복적정도수Bi3＋량적증가이증강，거차건립료양화석묵희-아갑기람형광광도법측정Bi3＋적신방법。고찰료아갑기람、양화석묵희농도，산도이급시제가입순서대체계형광회복적영향，해락합체계적격발파장위667 nm，발사파장위690 nm，재우화조건하，Bi3＋적농도재0．5～100μmol·L-1범위내여형광강도정량호적선성관계，상관계수위0．9955。방법적검출한위1．0×10-8 mol· L-1（S/N＝3）。평개료해방법적선택성，결과표명당공존리자위1000배적K＋，Ca2＋，Na＋，Mg2＋，Cu2＋；100배적Fe3＋，Be2＋，SiO2-3，Al3＋，Ni2＋，Sb3＋，NO-3，Cl-，F-；20배적Pb2＋，Hg2＋，Cd2＋불간우Bi3＋적측정，신방법구유령민도고、쾌속、성본저등우점，장제출적방법용우배경수양적분석，회수솔위93．4％～105．2％。
Graphene oxide was prepared by the modified Hummers method and characterized by field emission scanning electron microscopy.The interaction of graphene with methylene blue was studied by UV absorption,the intensity of two main absorp-tion peaks of methylene blue decreased significantly after the fluorescence was quenched,and the energy transfer didn’t occur be-cause the overlap of the absorption spectrum of GO and the emission spectrum of MB is too small.Therefore,the fluorescence quenching of MB and GO was static.When adding a certain amount of Bi3+ in the graphene-methylene blue system,Bi3+ replaces the methylene blue from the graphene-methylene blue complexes because Bi3+ has the smaller volume and is more positively charged.The methylene blue therefore dissociates from the GO-MB complexes,resulting in the recovery of fluorescence of the system.Furthermore,the fluorescence of the system increases with the increase in the amount of Bi3+ due to the enhanced amount of MB in the system.A novel spectrofluorimetric method was therefore developed for the sensitive determination of Bi3+.Some parameters including the concentration of methylene blue,the amount of graphene oxide,the amount of nitric acid and the sequence of reagent adding were optimized to obtain higher sensitivity.The fluorescence of the system was detected at an emission wavelength of 667 nm with excitation at 690 nm.Under the optimized conditions,the concentration of Bi3+ showed good linear relationships with the fluorescence intensity in the range of 0. 5~100μmol·L-1 ,with correlation coefficients of r=0. 995 5.The limits of detection for Bi3+ was 1. 0×10-8 mol·L-1 (S/N= 3).The selectivity of the proposed method was evalu-ated and the results showed that 1 000-fold K+,Ca2+,Na+,Mg2+,Cu2+;100-fold Fe3+,Be2+,SiO2,- Al3+,Ni2+,Sb3+, NO-3 ,Cl-,F-,and 20-fold Pb2+,Hg2+,Cd2+ had negligible interference with the determination of Bi3+.The method has ad-vantages of sensitivity,rapidness and low cost.It was used for the determination of Bi3+ in environmental water samples inclu-ding pond water,rain water and sewage water with recoveries of 93. 4%~105. 2%.
